// Albert Einstein said: "If you can't explain it to a six year old, you don't understand it yourself." I like to think this is true about explaining things to my parents - Isn't this a quote by Richard Feynman?
> Feynman was a truly great teacher. He prided himself on being able to devise ways to explain even the most profound ideas to beginning students. Once, I said to him, “Dick, explain to me, so that I can understand it, why spin one-half particles obey Fermi-Dirac statistics.” Sizing up his audience perfectly, Feynman said, “I’ll prepare a freshman lecture on it.” But he came back a few days later to say, “I couldn’t do it. I couldn’t reduce it to the freshman level. That means we don’t really understand it.”
– Feynman’s Lost Lecture by David and Judith Goodstein